Anthony Breach is a Senior Analyst at Centre for Cities, where he leads on housing and planning.
The green belt has popped back up in the news, along with the familiar pledges from politicians to protect it.
But unlike previous debates, there has been a pushback, including on these pages.
As Robert Colville has pointed out both online and in the Times, the green belt covers 12 per cent of England – more than all of England’s developed land and infrastructure at eight per cent – and for the green belt to disappear at current rates of release would take over 1,000 years.
In short, the consensus that the green belt should be protected at any cost is beginning to break down as the sheer size of those costs have become visible, especially to younger voters. If we want to understand these costs and how it should inform policy however, we first must consider the green belt’s benefits and purpose.
Contrary to popular belief however, the green belt does not protect special parts of the countryside. Other planning designations such as Areas of Outstanding Natural Beauty, National Parks and Sites of Special Scientific Interest, among other designations, do that.
Instead, the purpose of the green belt is urban containment. The Government clearly states in the green belt’s five objectives that it exists to restrict of the growth of cities and urban economies. The economic costs of the green belt are therefore much sharper than for other parts of the planning system, which aim to protect natural environments, because the green belt explicitly exists to reduce economic activity.
Of course, the green belt does provide some non-economic benefits. Even if it struggles to achieve some of its objectives – for example it does not aid the recycling of urban land due to problems in other parts of the English planning system – it does successfully achieve its purpose of preventing development in the countryside.
These benefits must be considered, however, against the unreformed green belt’s costs across at least four areas: it makes housing more expensive; it reduces the land available for industrial activity; it prevents brownfield redevelopment within the green belt; and it damages the environment by forcing suburbia to sprawl.
The green belt makes housing in England much less affordable because it reduces supply, especially in the most prosperous parts of the country with the most potential for economic growth.
This has been understood since Sir Peter Hall’s work on the green belt in the 1960s and 1970s, but more recent evidence from Hilber and Vermeulen estimates that house prices in 2008 in the South East of England (where London’s green belt covers an area three times the size of Greater London) would be 25 per cent lower if the land supply was as flexible as that as the North East of England, which is still highly restrictive by international standards.
Accordingly, the restrictions the green belt imposes on development have been felt in a growing backlog of unbuilt housing that every year makes the housing market just a little bit worse and more expensive than the previous year, especially for younger people.
For instance, space per private renter in England fell from 367 ft2in 1995 to 307 ft2 in 2018, and in London from 329 ft2 to 264ft over the same period, even as homeownership rates fell.
These trends are not driven by immigration either. For example, if England (which currently builds around 220,000-240,000 new homes a year, the highest in decades) wanted the same ratio of people to dwellings as France (which builds roughly 380,000 a year, a decline from a recent peak of nearly 500,000 before the financial crisis), then England would need to build over six million more homes just to overcome the backlog, even if net immigration dropped to zero.
Furthermore, decades of “brownfield-first” policy, pursued to delay green belt reform, has finally exhausted London’s stock of brownfield land, with knock-on costs for employment and growth. The classic urban regeneration strategy of building new homes on industrial land is no longer viable in London, as the combination of the green belt’s restrictions on land-use and rising demand from logistics has pushed industrial land values per acre above residential for the first time in decades.
An additional cost is that the green belt actually makes brownfield development harder. Just as greenfield – never previously developed – land can sit outside the green belt, land can be brownfield – previously developed – and sit within the green belt.
It is easy to find examples of this: an open letter signed by the IEA, ASI, and Taxpayer’s Alliance among others has identified petrol stations and waste sites next to tube stations, which are protected by the green belt despite the economic and social costs of doing so.
As the green belt exists to make cities smaller rather than to protect nature, it also accidentally damages the environment. The new homes that are built to allow people to access suburban living near city centre economies are forced to “leapfrog” the green belt, such as from London to Bedford or Wiltshire, inducing unnecessary urban sprawl and longer commutes by car.
Unlike nature reserves, much of the green belt is monoculture cropland, and does not offer the ecological benefits that parks, gardens, and other urban green spaces provide.
Overarching these problems is that the green belt does not just impose significant economic costs – it also induces political conflict in the planning process. The green belt’s rigid rules make it much more difficult than it should be for local and national government to deliver housing, jobs, and public services, especially in affluent areas.
Proposals to make tiny changes to green belts in local plans consume enormous amounts of time, resource, and political capital, with much effort by local government going into “planning” but little actual planning of infrastructure or public satisfaction in planning.
There are improvements we can make to these planning processes without touching the green belt. Some ideas that will improve public support for new housing are Clause 83 and 84 in the Levelling Up Bill and London Yimby’s Street Votes proposal. Real supply-side reform always depends on tough choices though, and it is difficult to see how Britain’s housing and urban land problems can be fixed while politicians avoid reforming green belt despite growing calls for change.
There are lots of ideas on the table for open-minded and bold politicians. Land swaps could release land for new homes and industrial uses close to city economies to create jobs and cheaper, while protecting remote and fragile countryside. Bold politicians who want to go further may want to consider a refresh of the green belt’s objectives, or whether an urban-containment designation should apply within urban local authorities.
In contrast to the economic costs of the green belt, the costs of reform are small, and the potential benefits are large.
For example, in a paper for the Centre for Cities, Professor Paul Cheshire and Boyana Buyuklieva were able to calculate that between 1.7 to 2.1 million new homes could be built for suburban living (40 to 50 homes per hectare) on both green belt and unallocated land within 800 metres around train stations within 45 minutes of the city centres of London, Manchester, Birmingham, Bristol, and Newcastle.
This would increase England’s total housing stock by between seven and nine per cent and use less than 1.8 per cent of the green belt, while protecting AONBs, National Parks, etc. and providing new public green space for residents.
Ultimately though, the costs of the unreformed green belt are too high to ignore, and the public is no longer ignoring them. Politicians need to be clear about not just what they like about the green belt and how they plan to protect it, but also what they want the green belt to do and how they aim to address the costs it imposes on the country.